Japan Earthquake: nuclear plants

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  • #12,201
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Sorry, I can't do it as it seems :-( The trick requires plenty (hundreds) of frames about the same view, and - due the spherical distortion of the cam - from the same position. There isn't enough of this kind of frame series in the released videos. Even small movements are problematic, because the noise prevents any automated alignment algorithm to be effective.

There will be only a dozen 'enhanced' picture soon, but most of them from different viewpoints. They will not fit for a mosaic.

About the scale: what's illuminated there is close to the cam. This can give a hint. I think the yellowish tubes are ~ 1 inch, the brown packed ones maybe 2 inch in diameter.
You may be right. I'm not trying to be argumentative, but how do you make those estimates? What do you know anout the focal length and distance from the lens?
 
  • #12,202
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If you are referring to its slightly curved appearance in that image, I think we'd need to take into strong account the possibility of slight image deformation caused but the lens setup of the endoscope.
If you take a ruler, the other support structure or pipe, more dark, is curved as well, but in the opposite direction, so either it's the lens as you said, or we are watching the side of the RPV and so it is really curved (I'm no expert to say that), or (but I believe less) they deformed.

However, what drew my attention was the brownish spot. From the shadow it looks as if the side of the support is broken, either rusted (but isn't it too brilliant for being rust?) or melted
 
  • #12,203
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You may be right. I'm not trying to be argumentative, but how do you make those estimates? What do you know anout the focal length and distance from the lens?
I don't know anything about the cam itself. But there are plenty of hints on the pictures:
- as the camera light illuminates the various objects, depending on the distance
- the water drops and flows on the objects (for example on the picture about the packed brown pipes you can see some drops hanging on that belt-like object, and if you check the videos, you can see some water flows on the yellowish tubes too)
- rust spots
- the deposite on the containment wall (what also calibrates the strength of the light)

It was not really an estimate based on science.

If you are referring to its slightly curved appearance in that image, I think we'd need to take into strong account the possibility of slight image deformation caused but the lens setup of the endoscope.
Those lens has some brutal spherical distortion. If you check those tubes as the cam moves, they bend differently on every frame. That's why I couldn't easily stack together enough frames to average out the noise.

However, what drew my attention was the brownish spot. From the shadow it looks as if the side of the support is broken, either rusted (but isn't it too brilliant for being rust?) or melted
Wet rust is brilliant, that's OK. But melted... I don't think. There is a concrete wall between the cam and the bottom of the RPV, so I don't expect to find any melted object.

About the rust: here is a photo about a drywell of Browns Ferry NPP:
http://umners.files.wordpress.com/2011/03/a.jpg

Some (less critical) items there are clearly not built with the best material available, so rust attack seems possible (especially at high temperatures and with seawater).
Also there are some stacked brown pipes at the right side.
 
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  • #12,205
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I checked the weather for then, and the radiation spiked occurred during a time when it was snowing in Tsukuba, AND the wind was blowing straight from Fukushima Daiichi. (By the way, the radiation started to rise before the earthquake, so that is probably not the cause. And the radiation stopped when the snow stopped.) Similar to previous spikes associated with precipitation and wind coming from F1.

Someone in Tokyo also apparently saw a rise there (further downwind from Tsukuba), did an isotope analysis, and found it was Lead-214 and Bismuth-214 -- radon daughter products. Obviously they weren't kicked up out of the ground (it was snow this time, not rain), but apparently swept out of the air.

Seems nothing to worry about, but kind of curious -- is it possible that the big pile(s) of scrap uranium at Fukushima Daiichi is serving as a giant radon source? Just from decay of the exposed uranium.
 
  • #12,206
tsutsuji
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http://www3.nhk.or.jp/news/genpatsu-fukushima/20120125/index.html On 25 January, the 9-member government's investigation committee held its first (non public) meeting since the release of the interim report. At the end of February they will hold a meeting with foreign specialists, hearing their opinions, which could result in adding new investigation topics. The final report is expected for the end of July.
 
  • #12,207
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Someone in Tokyo also apparently saw a rise there (further downwind from Tsukuba), did an isotope analysis, and found it was Lead-214 and Bismuth-214 -- radon daughter products. Obviously they weren't kicked up out of the ground (it was snow this time, not rain), but apparently swept out of the air.

Seems nothing to worry about, but kind of curious -- is it possible that the big pile(s) of scrap uranium at Fukushima Daiichi is serving as a giant radon source? Just from decay of the exposed uranium.
Interesting analysis. I suppose it's possible that the melted fuel is liberating radon into the water which is being carried out of containment and being released into the air, but I would also wonder if the same effect is visible with snowfalls with the wind in other directions. Maybe this is just within the bounds of a normal precipitation effect.
 
  • #12,208
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I am not sure what this means and where it comes from. Unfortunately there are a lot of stupid statements around on the Enenews page, so it is neither a reliable source of information nor a big help to me...

One can also clearly see this radiation spike in the Tokyo graph, but the level is back to normal now:

http://http://monitoring.tokyo-eiken.go.jp/monitoring/graph.html
 
  • #12,210
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Interesting analysis. I suppose it's possible that the melted fuel is liberating radon into the water which is being carried out of containment and being released into the air,
The radon could escape directly to the atmosphere from the holes in containment (the ones from which the steam was coming last year), couldn't it?

but I would also wonder if the same effect is visible with snowfalls with the wind in other directions. Maybe this is just within the bounds of a normal precipitation effect.
Could be, though there have been plenty of rain events in the past year without any associated spike in radiation. The spikes only seem to be associated with being downwind of F1, at least the ones that I have checked in the past.

As for moving this to the contamination and consequences thread, I'm not sure I would classify a whiff of short-lived radon daughter products as contamination, and it does not appear very consequential. I consider this more in the realm of "remote sensing" of what may be going on at the plant -- if it can be determined to be from the plant.

The other possibility that occurs to me is that there is also an old uranium mine (from the war) in Fukushima near the airport, and there is also a radon onsen near there, so maybe it is possible the wind blew some radon from there instead. Not as directly upstream of Tsukuba as F1 was at the time of the spike, but not completely out of the stream either. I'll post some wind maps later to show what I mean.

In any case it would be good to have an explanation of what is going on, so people don't need to freak out next time this happens. (In that sense, perhaps it does belong in the contamination and consequences thread.) It is also just interesting.
 
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  • #12,211
tsutsuji
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Sorry for the off-topic, but what were the applications of uranium at the time of that "old uranium mine (from the war)" in Fukushima prefecture ?
 
  • #12,213
jim hardy
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their Manhattan Project was moved to North Korea because we kept bombing Tokyo where their labs were located..
It's believed that at war's end it was packed up and sent to Stalin.
though old anecdotes of a test exist.

One can search for some of Dr Paul Kuroda's memoirs. He was a minor researcher in Japan's bomb effort who came here after the war, worked on astrophysics.

old jim
 
  • #12,214
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The other possibility that occurs to me is that there is also an old uranium mine (from the war) in Fukushima near the airport, and there is also a radon onsen near there, so maybe it is possible the wind blew some radon from there instead. Not as directly upstream of Tsukuba as F1 was at the time of the spike, but not completely out of the stream either. I'll post some wind maps later to show what I mean.
After doing some more research, it turns out there are several radon onsens dotted around the eastern half of Fukushima prefecture, including one in Hirono, about 20 km south of the Fukushima Daiichi power plant. So, there are likely to be uranium ores distributed over a rather wide area in the ground. In fact, there is even a radon onsen in Mito in Ibaraki prefecture, much closer to Tsukuba than anywhere in Fukushima, and also upwind of it that day.

So, unless someone has a calculation showing that the expected radon concentration from Fukushima Daiichi should be much higher than that from the natural emanations coming out of the ground in the general region, the significance of these precipitation-related radiation spikes would seem to be inconclusive.
 
  • #12,216
tsutsuji
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http://www3.nhk.or.jp/news/genpatsu-fukushima/20120128/index.html on 28 January at 10:30, a 9 litre leak was found close to one of the 3 pumps that inject water into the reactors. The leak stopped after shutting the pump down. There was no flow into the sea. Then near noon, two other leaks were found on valves at the water processing facility. In both cases a few litres of processed water leaked, but remained inside the building(s).
 
  • #12,217
News seem to dry up, but there should be some activity.

For example, what's the status of basement water level reductions? How many tons are still there?

The plan was to seal off reactor building basements, to at least stop leaking into turbine buildings and further into the ground. Is there progress?

On this video I see that TEPCO is doing something around Unit 4:

Are these preparations for dismantling the ruined top part?
 
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  • #12,218
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Thanks for these questions nikkkom and I hope there is some activity. I asked something similar already, as I wonder if enough progress is made. Well, one could also wait 300 years until most of the radioactive stuff has decayed away...

And I also wonder about the plan for the accumulated water. There is still a high inflow of groundwater and soon the storage tanks will be full. And then?
 
  • #12,219
etudiant
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Afaik, the JAIF provides the best ongoing summary of the situation on its web site.
http://www.jaif.or.jp/english/
It indicates some 200,000 cubic meters of water have been treated, but the ongoing influx of groundwater means 80,000 cubic meters remain in the facility continually.
TEPCO is building a sea wall to seal off the site from the ocean, but the larger issue of sealing off the entire site from groundwater has yet to be tackled. It is not happening imho because it would be a monster job whose utility could be destroyed in an instant by another small earthquake.
The cleaned water probably will eventually be used as irrigation water, as the idea of dumping it into the ocean has encountered objections by the local fisheries. There is no public plan for what to do with the concentrated waste water or the contaminated filters and sludge material.
 
  • #12,220
tsutsuji
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News seem to dry up, but there should be some activity.

For example, what's the status of basement water level reductions? How many tons are still there?
Their mid-term goal is not to reduce water levels but to keep them stable : "based on the view of limiting inflow of underwater to buildings and reducing the amount of emerged accumulated water, we are planning to transfer accumulated water keeping its level in the building below OP. 3,000 considering water tank capacity." : http://www.tepco.co.jp/en/press/corp-com/release/betu12_e/images/120125e5.pdf
The plan was to seal off reactor building basements, to at least stop leaking into turbine buildings and further into the ground. Is there progress?
On http://www.tepco.co.jp/en/press/corp-com/release/betu11_e/images/111221e14.pdf page 42/94, "Target:Complete Switch to Water Withdrawal from Reactor Building (or lower part of PCV)" is set for mid-fiscal year 2015. There is also "(HP1-1): Completion of stopping inter-building water leakage between reactor and turbine buildings and repairing lower part of the PCV" which is planned for the middle of phase 2 around 2017. On page 48/94 you can see that "R&D for PCV Leakage Point Survey/ Repairs (including stopping inter-building water leakage)" is scheduled for fiscal years 2012-2013-2014 including "Design, Manufacture and Test, etc. of PCV Leakage Point Survey Equipment ②" and "Design, Manufacture and Test, etc. of PCV Repair Equipment ③⑥", with "Investigation of Leakage Points (including field test of R&D results)" starting in mid fiscal year 2014.

In the documents of the mid-long term meeting of 26 December you can find a slideshow about accumulated water : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/m111226_08-j.pdf page 16/37 - 24/37. It is divided into 3 parts:

1) Radical countermeasures against inflow of groundwater : they want to repair the subdrains that were damaged by the tsunami, then decontaminate them, and finally pump ground water from the subdrains to control ground water level and reduce ground water inflow into the turbine buildings.
2) Increase removal capacity and secure stable operation of decontamination facility
3) Further install on-land equipments. (The red areas are already used. The blue areas are still free for adding more tanks)

There was a second mid-long term meeting on 23 January. The documents are available on Japanese only (as far as I know) at http://www.tepco.co.jp/nu/fukushima-np/roadmap/conference-j.html (for example including the following presentations on mock-up debris : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_04-j.pdf and water treatment secondary waste products (sludge, zeolite) : http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_05-j.pdf and an announcement of a workshop on fuel removal techniques (open to the public and press) to be held on 24 February http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/r120123_06-j.pdf ).

There is also a detailed review of what was done during the past 30 days up to January 23, and what they plan to do in the coming months at http://www.tepco.co.jp/nu/fukushima-np/roadmap/images/m120123_05-j.pdf, which includes a report on the water levels of unit 4 pool, drywell pit, and skimmer surge tank, and another report on the installation of new water-treatment facilities (tanks, or waste storage areas), and new areas to store wood from the cleared forests. The trial run of unit 3's PCV gas managing system is scheduled for February 23. The "basic design of shortening the water injection loop" is mentioned as a continuous line from January through April, or possibly later. The basic design of the multi-nuclide removal equipment [1] ends at the end of January, and the detailed design of the same starts in February. A forest clearance is more or less scheduled at the end of February in connection with this multi-nuclide thing. A subdrain purification test was started at unit 2 in the second week of January. There is a plan to change the seismic isolated building into a zone outside the controlled area, which means decontaminating (like cleaning the roof) and shielding the building (with steel and lead sheets). The design for the shielding ends at the end of January. At unit 4 reactor building, in January, they took care of the top part of the operating floor crane and removed rows R5 and R6 of the roof steel frame [this is on the south side]. In February they will remove rows R3 and R4, and remove "big machines" from the operating floor. They will start removing unit 4's north side wall and steel frame at the end of March.

[1] an equipment that would remove strontium, according to http://www.japantimes.co.jp/text/nn20120112a9.html

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120129/index.html On 29 January Tepco announced 14 leaks [!]. It is believed that these leaks are due to the frost. One of them is a 40 litre leak found at unit 4 at 9:30 AM. Another one is a 600 litre leak found near one of the pumps that inject water into the reactors. Another one is a 7 ton leak of the circulating water of unit 6 (not contaminated). In the morning of 29 January, the temperature was 8°C of frost. Tepco's Junichi Matsumoto said "the freezing countermeasures are far from being sufficient. It is necessary to install heat insulating material at a higher pace than until now".

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120129_01-e.pdf "Water leakage in Fukushima Daiichi Nuclear Power Station (Discovered on 29 January)"

http://www.tepco.co.jp/en/nu/fukushima-np/images/handouts_120129_02-e.pdf (map of the leaks)
 
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  • #12,221
Afaik, the JAIF provides the best ongoing summary of the situation on its web site.
http://www.jaif.or.jp/english/
It indicates some 200,000 cubic meters of water have been treated, but the ongoing influx of groundwater means 80,000 cubic meters remain in the facility continually.
Uhhh... that's an awful lot of water. The influx is so large? Why?

the larger issue of sealing off the entire site from groundwater has yet to be tackled. It is not happening imho because it would be a monster job whose utility could be destroyed in an instant by another small earthquake.
Did it occur to TEPCO to drill a few dozen drainage wells and pump them out?

Do they really plan to keep basements drenched wet for five years or more? That stuff wasn't designed for this environment! Everything will rust into dust!
 
  • #12,222
The cleaned water probably will eventually be used as irrigation water, as the idea of dumping it into the ocean has encountered objections by the local fisheries.
Somehow I think local farmers won't be happy either. In fact, dumping this very slightly contaminated water into the ocean is the best idea. If this will not be allowed, is it economical to distillate it once more?
 
  • #12,223
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...is it economical to distillate it once more?
IIRC the remaining contamination is partly Tritium, which cannot be removed easily.

Did it occur to TEPCO to drill a few dozen drainage wells and pump them out?
To prevent further contamination outside the containment they prefer water flowing in. This way they will have to deal with some more water: the other way would mean awful lot of contaminated ground beneath the buildings.

It's a kind of similar system which used in biology or chemistry. Inflow is better when you want to keep something inside.
 
  • #12,224
tsutsuji
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http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/2130_4kasyo.html Tepco found 4 more leaks in the night of 29 January and on 30 January. The temperature in the morning of 30 January was 8.7°C of frost. Tepco is reinforcing patrols and covering pipes and equipments with insulating material. Junichi Matsumoto said "as the severe frost is expected to continue, we want to urgently take countermeasures against freezing in the places that were not reached by those countermeasures".

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/0730_mizumore.html The NISA has ordered Tepco to take countermeasures against frost in response to the 14 leaks discovered on 29 January, implying a 1 hour 40 minutes stop of unit 4's cooling system. In all cases either pipe junctions were loosened or parts were broken by the expansion of water caused by freezing. Tepco is increasing patrols, adding insulating material and, in some cases, heaters. At the important equipments such as those that perform reactor cooling and those that involve highly contaminated water, the countermeasures are almost complete, but as the frost is expected to continue for several days, Tepco is hurrying up with the remaining countermeasures.

http://www3.nhk.or.jp/news/genpatsu-fukushima/20120130/1845_robo.html Chiba institute of Technology has developped robots Quince No.2 and No.3. They were urgently developed after Quince No.1 had its cable entangled and could not move any more inside unit 2 in October. They have nearly the same shape and size as Quince No.1, but cable entanglement is being made more difficult. In case cable communication is impossible, they can communicate with another robot by radio. Quince No. 2 is equipped with a high sensitivity radiation measurement equipment, and Quince No. 3 with a scanner to measure distances. Quince No.2 and No.3 will start being used in mid-February.

http://www.tokyo-np.co.jp/article/feature/nucerror/condition/list/CK2012012902000091.html?ref=rank [Broken] [29 January] During the week from 22 January to 28 January, the cesium released into the atmosphere by Fukushima Daiichi increased in comparison to the December level. The radiation released by units 1, 2, and 3 all together was 72 million Bq/hour , which is 12 million Bq/hour higher than in December. It is said that as more work was done inside units 2 and 3, the cesium accumulated on the floor soared into the air. Until then cesium release quantities had been steadily decreasing. Tepco said "It is difficult to dramatically decrease the releases. For the time being, the present level will be continuing". To prevent the spreading of the cesium accumulated on the sea floor, the sea floor in the harbour in front of the plant will be covered with a 60 cm thick layer of clay and cement. This work will be done from mid-February to March.

http://www.asahi.com/national/update/0130/TKY201201300070.html According to a November survey, the cesium concentration in the sea floor in the harbour is up to 1.6 million Bq/kg. The 60 cm thick cement layer will cover a 7 Ha area. The local fishing cooperatives had expressed worries that the construction work of the ground water shielding wall would spread cesium into the sea.
 
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  • #12,225
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Thanks tsutsuji!

By the way, what happened to Quince No.1, was it left in Unit 2?
 

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